Habitat:Saccharomyces when
translated means “sugar fungus”. That is what this yeast uses for food. They are
found in the wild growing on the skins of grapes and other fruits.

Means for Classification:
Saccharomyces cerevisiae is in the fungi kingdom. The reasons for this
classification are because it has a cell wall made of chitin, it has no
peptiodglycan in its cell walls, and its lipids are ester linked. It also uses
DNA template for protein synthesis and it has larger ribosomes. It is then
consider a yeast because it is a unicellular organism so it can not form a
fruiting body; like other fungi.

Adaptations:Saccharomyces
cerevisiae has adapted in several important ways. One is the fact that they
are able break down their food through both aerobic respiration and anaerobic
fermentation. They can survive in an oxygen deficient environment for a period.
Another adaptation they have is their ability to have both sexual and asexual
reproduction. Very few other Ascomycota can do both processes. And very few
organisms can do all four of these processes. This allows this species to live
in many different environments. (Madigan, 457)

Nutrition: Saccharomyces
cerevisiae gets its energy from glucose.

Life Cycle:
Saccharomyces cerevisiae has both asexual and sexual reproduction.

In asexual reproduction the
haploid of the yeast under goes mitosis and forms more haploid yeasts. There is
an a and ά strain of these haploids. Then these haploid yeasts, one from each
strain, can fuse together and become on cell. Then the nuclei of both cell fuses
together and this cell is now the zygote. These diploid cells can go through
mitosis, which they call budding, and four more zygotes or they can under go
meiosis and from an ascus which will split into four ascospores. These haploids
can then under go germination and become haploid yeast again. (Madigan, 457)

Importance: Saccharomyces
cerevisiae is one of the most important fungi in the history of the world.
This yeast is responsible for the production of ethanol in alcoholic drinks and
is the reasons your mother’s bread dough rises in the pan. That is where the
names brewer’s and baker’s yeast come from. The process in which it produces
ethanol is one way this yeast converts glucose into energy. There are two ways
Saccharomyces cerevisiae breaks down glucose. One way is through aerobic
respiration. This process requires the presence of oxygen. When oxygen is not
present the yeast will then go through anaerobic fermentation. The net result of
this is two ATP, and it also produces two by products; carbon dioxide and
ethanol. So if this yeast is allowed to grow in a container lacking oxygen it
will produce ethanol (alcohol). Humans have been isolating this process since
the beginning of history. The yeast helps in the rising of bread with it’s other
by-product carbon dioxide. The gas that is produce inside the dough causes it
to rise and expand. Both of these processes use the haploid of this yeast for
this process. In industry they isolate one strain, either a or ά, of the haploid
to keep them from undergoing mating. (Madigan, 457) In the baker’s yeast they
have a strain were the production of carbon dioxide is more prevalent then
ethanol and vice versa for brewing. (Tomvolkfungi.net) Another importance is
that “live
yeast supplementation to early lactating dairy goats significantly increased
milk production”. (Stella, A.V.;1)